I've been on iOS 6 since it came out to devs, so don't think it is that, but am having the same issue. Wondering if it is related to one of my many app updates that have been applied in the past couple of hours.

Try to get onto wifi and pulls up apple.com, page not found, then defaults back to 4G.

Same problem with me. Tried resetting my Airport thinking it was an error there, and then wondered if it was the heavy lightning/thunder in Miami, but now that I see this I see it's more widespread. How strange though that it started now all of a sudden...

Exact same but my phone worked fine for several hours, wife got home and updated hers and now mine can't connect. Mac was having problems for a few minutes, had to restart base station and it can get back on, still no phones

Dito here. Upgraded my iPad 2 and iPhone 4, and neither will join any wifi networks other than the one at work when I updated my devices. Perhaps something to do with the setup procedure and then updating the apps afterwards?

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